Water film evaluation method, and antifogging agent evaluation method

Abstract

A method for evaluating water film is a method for evaluating water film uniformity, and the method includes: a first step of preparing a base material for water film formation having a principal surface for forming a water film thereon; a second step of capturing an image of an object having a pattern in which a plurality of regions having predetermined brightness are disposed in a predetermined area, through the base material for water film formation having a water film formed on the principal surface, to obtain an image for evaluation; and a third step of deriving a water film uniformity index indicating uniformity of the water film based on the area distribution of the regions having predetermined brightness in the image for evaluation.

1 . A method for evaluating water film for uniformity, the method comprising:
 a first step of preparing a base material for water film formation having a principal surface for forming a water film thereon;   a second step of capturing an image of an object having a pattern in which a plurality of regions having predetermined brightness are disposed in a predetermined area, through the base material for water film formation having a water film formed on the principal surface, to obtain an image for evaluation; and   a third step of deriving a water film uniformity index indicating uniformity of the water film based on an area distribution of the regions having predetermined brightness in the image for evaluation.   
     
     
         2 . A method for evaluating antifogging agent, the method comprising:
 a first step of preparing a sample by treating a principal surface of a base material with an antifogging agent;   a second step of capturing an image of an object having a pattern in which a plurality of regions having predetermined brightness are disposed in a predetermined area, through the sample having a water film formed on the principal surface treated with the antifogging agent, to obtain an image for evaluation; and   a third step of deriving a water film uniformity index indicating uniformity of the water film based on an area distribution of the regions having predetermined brightness in the image for evaluation,   wherein when the water film uniformity index is equal to or higher than a predetermined threshold value, the water film uniformity of the antifogging agent is considered high.   
     
     
         3 . The method for evaluating antifogging agent according to  claim 2 , wherein the method for evaluating antifogging agent is used for evaluating water film uniformity of an antifogging agent capable of forming a film having a contact angle against water of 10° or less. 
     
     
         4 . The method for evaluating antifogging agent according to  claim 2 , wherein the method for evaluating antifogging agent is used for evaluating water film uniformity of an antifogging agent including silica. 
     
     
         5 . The method for evaluating antifogging agent according to  claim 2 , further comprising:
 a fourth step of applying a fog generating means capable of generating fog on the untreated base material, to the principal surface of the sample prepared in the first step, and then capturing an image of a predetermined object through the sample to obtain an image for antifogging properties evaluation; and   a fifth step of deriving an antifogging index indicating the antifogging properties of the antifogging agent on the basis of a file capacity at the time of compressing the image for antifogging properties evaluation by a predetermined compression method,   wherein the second step and the third step are carried out when the antifogging index is equal to or higher than a predetermined threshold value.   
     
     
         6 . The method for evaluating antifogging agent according to  claim 3 , wherein the method for evaluating antifogging agent is used for evaluating water film uniformity of an antifogging agent including silica. 
     
     
         7 . The method for evaluating antifogging agent according to  claim 3 , further comprising:
 a fourth step of applying a fog generating means capable of generating fog on the untreated base material, to the principal surface of the sample prepared in the first step, and then capturing an image of a predetermined object through the sample to obtain an image for antifogging properties evaluation; and   a fifth step of deriving an antifogging index indicating the antifogging properties of the antifogging agent on the basis of a file capacity at the time of compressing the image for antifogging properties evaluation by a predetermined compression method,   wherein the second step and the third step are carried out when the antifogging index is equal to or higher than a predetermined threshold value.   
     
     
         8 . The method for evaluating antifogging agent according to  claim 4 , further comprising:
 a fourth step of applying a fog generating means capable of generating fog on the untreated base material, to the principal surface of the sample prepared in the first step, and then capturing an image of a predetermined object through the sample to obtain an image for antifogging properties evaluation; and   a fifth step of deriving an antifogging index indicating the antifogging properties of the antifogging agent on the basis of a file capacity at the time of compressing the image for antifogging properties evaluation by a predetermined compression method,   wherein the second step and the third step are carried out when the antifogging index is equal to or higher than a predetermined threshold value.